Dr. Lukasz R. Niec (right) was detained by ICE at his Kalamazoo home on Tuesday, January 16, 2018. Photo courtesy Family Photos

By Madison Park and Emanuella Grinberg, CNN

(CNN) -- A Michigan doctor came under scrutiny from immigration authorities due to 18 police encounters, including a child abuse allegation, an official with US Immigration and Customs Enforcement told CNN -- but those claims were investigated by police and weren't substantiated.

Dr. Lukasz R. Niec has been in ICE custody since last week. He is a permanent resident, his family says. But he could be deported to Poland -- a country he's never known. Niec's family has launched a legal fight to keep him in the US and bring him home.

His lawyer, Russell Abrutyn, said about the abuse allegation: "From what I understand, the Michigan State Police investigated this allegation and found it to be without merit. We expect the child abuse investigation to be dismissed, too."

Michigan State Police confirm they did investigate an allegation of child abuse against Niec in 2017 and turned their findings over to the county prosecutor's office.

A charging request form filed with the Kalamazoo County prosecuting attorney says police found "insufficient evidence" and determined there was "no reasonable likelihood of conviction."

Niec's wife, Rachelle Burkart-Niec, also told CNN affiliate WWMT that the case had no merit.

Niec was 5 years old when his parents fled Poland in 1979, his sister, Iwona Niec-Villaire told CNN. He received a temporary green card and later became a lawful permanent resident, she added.

Niec entered the United States lawfully, ICE said but he was found "amenable to removal proceedings as a result of two 1992 state convictions for malicious destruction of property and receiving stolen property, both of which are crimes involving moral turpitude."

The statement defined a crime of moral turpitude as "a crime against a person (such as assault), fraud, perjury, robbery, theft and bribery." A crime of moral turpitude can be either a felony or a misdemeanor, it said.

He was 17 years old when he committed those offenses and one of the charges had been expunged from his record after he completed a youth training program, his family said.

Niec became a doctor, specializing in internal medicine for Bronson Healthcare Group in Kalamazoo.

ICE arrested him on January 16 over "administrative immigration violations," the agency said.

"He most recently came under agency scrutiny as a result of 18 encounters with local law enforcement. He will remain in ICE custody pending the outcome of removal proceedings," according to its statement.

In 2013, Niec was charged with domestic violence but was found not guilty by a Kalamazoo County District Court jury, according to court records obtained by CNN. Details of that case were not immediately available.

Niec was convicted of driving while intoxicated in 2008, records say. He completed his probation, paid a fine and the conviction was set aside, the records show.

He also was charged with 20 other minor traffic offenses, such as speeding or failure to change the address on his license, from 1997 to 2016, court records show.

While questions remain about Niec's immigration status, his background and the reason for his detention, his situation offers a cautionary tale for permanent residents with a criminal record, immigration lawyer Charles Kuck said.

Until you become a naturalized citizen, you're still eligible for deportation, he said. Legal permanent residents convicted of crimes have long been the targets of deportation orders.

"(Niec) is a microcosm of what's happening all over the country but doesn't get publicity until it happens to a white guy from Europe living in the suburbs," Kuck said.